Neurodegenerative conditions affect a significant portion of our society, especially among the aging population. Various tauopathies, including Alzheimer's disease, can lead to neurodegeneration. It is estimated that Alzheimer's disease currently affects 2.4 million to 4.5 million Americans, and this number is projected to more than triple to reach 16 million by mid-century. Although Alzheimer's disease is not a normal part of aging, the risk of developing the illness rises with age. Current research from the National Institute on Aging indicates that the prevalence of Alzheimer's disease doubles every five years beyond age 65. This disease impacts an increasingly larger percentage of Americans, as the number of people age 65 and older will reach 70.3 million by 2030, or 20% of the U.S. population; likewise, those 85 and older will rise to 8.9 million, according to the U.S. Census Bureau. To consider the impact of this disease from another perspective, it often requires one to four family members to act as caregivers for each individual with Alzheimer's disease.
Mental disorders affects our society in a similar manner. For example, schizophrenia, a disabling mental disease affecting approximately 1% of the world population and over 2 million people in America, is devastating for those who are afflicted and their families. Treating and maintaining patients suffering from schizophrenia is very costly for the families and society. In 2002, the cost for treating schizophrenia in the US alone was estimated to be $62.7 billion.
Because of the significant social and economical impact of neurodegenerative diseases and mental disorders, there exists a need for new and better methods for the diagnosis and monitoring of these conditions. The present invention fulfills these and other related needs.